Light Field Reversed

The essentials of the Raman scattering experiment are shown in Figure 1. An intense monochromatic light beam impinges on the sample. The electric field of the incident radiation distorts the electron clouds that make up the chemical bonds in the sample, storing some energy. When the field reverses as the wave passes, the... 

Adiabatically rotating the mixing angles 6 from 0 to 7t/2 leads to a complete and reversible transfer of all photonic states to a collective atomic excitation if the maximum number of photons n + m is less than the number of atoms N. Let the initial quantum state of the light field be described by the density matrix... 

Engelmann watched photosynthetic bacteria under the microscope which reversed their swimming direction when they left the irradiated field and entered a dark field as if frightened (13). The older literature is summarized by (14). Cells can be collected in a light field when the cells enter a light field from the surrounding dark area there is no response, but when they try to leave it they reverse their swimming direction. 

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